1. Technical Field
The embodiments herein generally relate to solar processing and characterization, and more specifically, to a high throughput combinatorial characterization tool for combinatorial test substrates.
2. Description of the Related Art
Some exemplary solar processing operations include operations for adding (depositions) and removing layers (etch), defining features, preparing layers (e.g., cleans), doping, etc. However, solar companies conduct research and development (R&D) on full substrate processing, often on very large substrates and requiring a complete solar cell manufacturing line. This approach has resulted in high R&D costs and the inability to conduct extensive experimentation in a timely and cost effective manner. Combinatorial processing as applied to solar manufacturing operations enables multiple experiments to be performed on a single substrate and without a complete solar cell manufacturing line. Equipment for performing the combinatorial processing and characterization of the combinatorial test substrates must support the efficiency offered through the combinatorial processing operations.
Combinatorial processing enables rapid evaluation of solar processing operations. The systems supporting the combinatorial processing are flexible to accommodate the demands for running the different processes either in parallel, serial, or some combination of the two. A valuable component of the systems for combinatorial processing are the characterization tools used to produce the data from high throughput experimentation in such a way that the process does not slow down. High performance combinatorial characterization tools are needed to quickly process and characterize the combinatorial test substrates.
Conventional solar electrical characterization such as internal quantum efficiency and external quantum efficiency measurements in a R&D environment is performed independently of one another in a manual and sequential mode. However, the conventional process tends to be time consuming and resource demanding resulting in a significant loss in testing throughput. For example, when there is a need for measuring multiple sites per sample, the throughput and resources of the operators becomes a critical issue. Taking 32 sites per sample as an example, it takes 30 minutes to measure the external quantum efficiency (EQE) per site. To finish the characterization of each example, the operator has to move the sites every 30 minutes for the next 16 hours. It is a lengthy and tiring test.